# Concepts **Lending and eTokens** Users lend assets like ETH, USDC, or DAI on XLend. In return, they receive **eTokens**, which represent their stake in the pool and accrue interest over time. eTokens can be transferred or traded. **Borrowing** Users can borrow assets by using their deposits as collateral. The **Loan-to-Value (LTV)** ratio determines how much can be borrowed against the collateral. **Health Factor** Liquidators monitor the **health factor** of each user’s position, which reflects the ratio of collateral to borrowed funds. If the health factor falls below a certain threshold, the position becomes at risk of liquidation. **Liquidation** If the collateral value drops too much, liquidators can buy the collateral at a discount to repay the loan. This helps keep the protocol solvent. **Advanced Features** * **eMode (Efficiency Mode)**: Allows borrowers to increase borrowing power when collateral and borrow assets are closely correlated (e.g., stablecoins). * **Isolation Mode**: Limits borrowing when new or volatile assets are used as collateral to reduce risk. [Read more](/extrafi-xlend/borrow-lend/isolation-mode.md). * **Supply and Borrow Caps**: Caps ensure that the protocol isn’t overly exposed to any single asset. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.extrafi.io/extrafi-xlend/borrow-lend/concepts.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.